Climate change brews ocean trouble

The year 1972 was a banner one for wheat farmers in the United States, a bad one for Peru's anchovy fishermen, and therein lies a cautionary tale about coastal fisheries, climate change, and their impact on America's pocketbook.

That was the year that the Nixon administration brokered a $750 million deal to export grain to its cold-war rival, the then-Soviet Union. This extra demand for wheat sent US food prices soaring. The increases, followed the next year by an Arab oil embargo and skyrocketing oil prices, contributed to the worst bout of inflation in the US since the end of World War II.

Today, marine scientist Andrew Bakun adds an under-appreciated twist. That year, he explains, a strong El Niño shut down the oceanic "dumbwaiter" off the Peruvian coast that brings cold, nutrient-rich water from great depths up to the surface. The anchovy population collapsed, depriving American farmers and ranchers of a key source of protein-rich feed for their livestock. That sent them to the grain markets as well, adding to the demand that drove up grain prices. The fishery collapse was temporary. But its economic effect lingered.

Evidence is starting to accumulate that global warming may contribute to – or even trigger – troubling ecological changes taking place in these key regions of coastal upwelling, where some of the world's richest fisheries exist.

These coastal upwelling regions – for example, off Peru, northern California, Oregon, and the west coast of Africa – collectively cover less than 1 percent of the ocean. But they But they account for 20 percent of the world's fish catch. Some of these areas have shown remarkable resilience, notes Dr. Bakun, with the Pew Institute for Ocean Science at the University of Miami in Florida. Others have not. The concern, he continues, "is when you might push the ecosystem just a little too far."

This concern has prompted an increased interest in exploring how these ecosystems respond to change.

from the Christian Science Monitor